The present invention relates to a water carbonator comprising a tubular container shaped such that it holds the plastic end plates without using any additional mechanical fastenings.
The water carbonators are well known apparatuses that serve to add carbon dioxide ratios to the water contained therein in order to thus obtain sparkling water, also commonly known as soda. They are substantially constituted by a container in which suitable passageways are formed such that there will be a CO2 inlet, a water inlet, a sparkling water outlet and suitable instruments for checking water level. A relief valve, due to the characteristics of pressurized tank with gas presence, is provided as well. The operation typically occurs by filling the container up with CO2 having a pressure ranging between 3 and 7 bars, then by letting the water entering, pushed by a higher pressure pump, through an orifice such that it is nebulized in the form of micro drops that offer a wide exchange surface and therefore gas absorption, the water having, due to Bernoulli effect, high speed. Suitable construction expedients, such as rebounding plates or tubes with holes at the nozzle level and particular profile at the end, are often inserted to raise to the most the water gassing.
The water level within the carbonator is kept such that in the upper portion there is always a CO2 amount. In order to obtain that result different systems are used: the most used system provide feelers that allow for detecting the presence of water between the feeler tip and the wall or other element connectable to an electronic system. They can be formed with one or two feelers. In the embodiment with two feelers, as the drawn water causes the level to fall below the longest feeler, the electronic system, which detects the dielectric between feeler and wall, actuates the pump operating till the level reaches the shortest feeler; in the embodiment provided with only one feeler, typical for carbonators having small capacity, some delays in the pump starting and stopping are added such that there is no instability due to the wave therein generated.
In the more common configuration the carbonators are formed with stainless steel having the pipe fittings, even formed with stainless steel, welded: from a technical standpoint this is the best solution but it has high manufacturing cost and the pipe fitting size is noticeable.
Alternative solutions were therefore studied having plastic parts which allow for forming the inlet and outlet passageways more easily and in a cost-effective manner.
The currently adopted solutions provide for making the container with a steel tube and a pair of head, also called end plates, of plastic material and held by tie rods that can be inside or outside the tube. The cheapest solution has just one central tie rod which holds both plates, but it is a solution having crack failure risk: two tie rods would assure of more reliability but would increase cost.